1. Field of the Invention
This invention relates to a magnetic recording method and apparatus for digital signals, a magnetic reproducing method and apparatus for digital signals for recording or reproducing digital signals for a magnetic tape, and a tape-shaped recording medium having recorded the digital signals.
2. Description of the Related Art
Recently, a camera built-in type digital video tape recorder for household use for recording digital video and audio signals on a magnetic tape, and an installed type digital video tape recorder for household use, are making their debut.
As a recording system for this type of the digital video tape recorder, there is known a format termed a DV system (IEC 61834 helical scan digital video tape cassette recording system using 6.35 mm magnetic tape for consumer (525/60, 624/50, 1125/60 and 1250/50 systems)). In this DV system, the tape width of the video tape in use is 6.35 mm (=xc2xc inch), which is narrower than the tape width of the video tape used in the conventional analog video tape recorder, such as the 8 mm system: IEC 60843 helical scan video tape cassette system using 8 mm magnetic tape for consumers. Notwithstanding the above mentioned fact, long-time recording with the picture quality higher than that possible with the conventional system is possible in the DV system because the recording signals are compressed and the recording density is increased in the DV system.
Meanwhile, the above-mentioned DV system is not compatible with the conventional analog video tape recorder, such as the 8 mm system. However, if the signals in the DV system can be recorded on a video tape of a wider tape width used in this conventional recording system, it is possible to record signals of higher picture quality for a longer time. On the other hand, if signals of the DV system can be recorded on or reproduced from the video tape used in the conventional recording system, it becomes possible to utilize resources such as production equipments or components of the video tape used in this conventional recording system.
It is therefore an object of the present invention to provide a method and apparatus for recording digital signals by which the conventional production equipment for magnetic tapes can be effectively utilized to record signals of high picture quality for prolonged time on the magnetic tape to facilitate additional data recording and editing.
It is another object of the present invention to provide a method and apparatus for reproducing signals of high picture quality recorded over a long time on a magnetic tape with the use of the conventional production equipment for magnetic tapes and for assuring facilitated additional data recording or editing.
It is yet another object of the present invention to provide a tape-shaped recording medium on which high quality signals have been recorded and on which data can be recorded additionally or edited easily.
In one aspect, the present invention provides a magnetic recording apparatus including recording data generating means for generating recording data in meeting with a digital recording format applied to a first magnetic tape of a pre-set tape width, extension data generating means for generating extension data for the recording data, and recording means for recording, on a second magnetic tape wider in tape width than the first magnetic tape, the recording data generated by the recording data generating means and the extension data generated by the extension data generating means. The recording means successively records, on a sole track formed on the second magnetic tape, the recording data of at least two tracks in the digital recording format generated by the recording data generating means and the extension data generated by the extension data generating means.
In the present magnetic recording apparatus for digital signals, recording data of at least two tracks in the digital recording format applied to a first magnetic tape and extension data are successively recorded on a sole track formed on a second magnetic tape wider in tape width than the first magnetic tape.
In another aspect, the present invention provides a magnetic recording method including generating recording data in meeting with a digital recording format applied to a first magnetic tape of a pre-set tape width, generating extension data for the recording data, and recording, on a second magnetic tape wider in tape width than the first magnetic tape, the recording data of at least two tracks in the digital recording format and the extension data.
In the present magnetic recording method for digital signals, recording data of at least two tracks in the digital recording format applied to a first magnetic tape and extension data are successively recorded on a sole track formed on a second magnetic tape wider in tape width than the first magnetic tape.
In still another aspect, the present invention provides a magnetic reproducing apparatus for digital signals including reproducing means for reproducing recording data and extension data for the recording data from a second tape having recorded thereon the recording data and the extension data and being wider in tape width than a first magnetic tape, wherein the recording data conforms to a digital recording format applied for the first magnetic tape of a pre-set tape width. The magnetic reproducing apparatus for digital signals also includes recording data processing means for processing the recording data reproduced by the reproducing means, and extension data processing means for processing the extension data generated by the reproducing means. The reproducing means successively reproduces the recording data of at least two tracks in the digital recording format from a sole track formed on the second magnetic tape.
In the present magnetic reproducing apparatus for digital signals, recording data of at least two tracks in the digital recording format applied to a first magnetic tape and extension data are successively recorded on a sole track formed on a second magnetic tape wider in tape width than the first magnetic tape.
In still another aspect, the present invention provides a magnetic reproducing method wherein the recording data of at least two tracks in a digital recording format applied to the a magnetic tape of a pre-set tape width and extension data for the recording data are successively reproduced from a sole track formed on a second magnetic tape, the second magnetic tape having recorded thereon the recording data and the extension data, the second magnetic tape being wider in tape width than the pre-set tape width. The magnetic reproducing method includes processing the reproduced recording data and processing the reproduced extension data.
In the present magnetic reproducing method for digital signals, recording data of at least two tracks in the digital recording format applied to a first magnetic tape and extension data are successively reproduced on a sole track formed on a second magnetic tape wider in tape width than the first magnetic tape.
In yet another aspect, the present invention provides a tape-shaped recording medium having recorded thereon recording data conforming to the digital recording format applied for a first magnetic tape of a pre-set tape width, and extension data, the tape-shaped recording medium being wider in width than the pre-set tape width. At least two tracks in the digital recording format are recorded on a sole recording track.
According to the present invention, the recording data of at least two tracks in the digital recording format applied for the first magnetic tape and the extension data are successively recorded or reproduced on or from a sole track formed on the second magnetic tape wider in tape width than the first magnetic tape, thus assuring recording of data of high data quality on the second magnetic tape for prolonged time, as well as effective utilization of resources, such as conventional production equipments or components. Since the speech signals and video signals can be recorded as extension data, these data can be additionally recorded or edited easily.